node/test/parallel/test-preload.js

var common = require('../common'),
    assert = require('assert'),
    path = require('path'),
    child_process = require('child_process');

var nodeBinary = process.argv[0];

var preloadOption = function(preloads) {
  var option = '';
  preloads.forEach(function(preload, index) {
    // TODO: randomly pick -r or --require
    option += '-r ' + preload + ' ';
  });
  return option;
}

var fixture = function(name) {
  return path.join(__dirname, '../fixtures/' + name);
}

var fixtureA = fixture('printA.js');
var fixtureB = fixture('printB.js');
var fixtureC = fixture('printC.js')
var fixtureThrows = fixture('throws_error4.js');

// test preloading a single module works
child_process.exec(nodeBinary + ' '
  + preloadOption([fixtureA]) + ' '
  + fixtureB,
  function(err, stdout, stderr) {
    if (err) throw err;
    assert.equal(stdout, 'A\nB\n');
  });

// test preloading multiple modules works
child_process.exec(nodeBinary + ' '
  + preloadOption([fixtureA, fixtureB]) + ' '
  + fixtureC,
  function(err, stdout, stderr) {
    if (err) throw err;
    assert.equal(stdout, 'A\nB\nC\n');
  });

// test that preloading a throwing module aborts
child_process.exec(nodeBinary + ' '
  + preloadOption([fixtureA, fixtureThrows]) + ' '
  + fixtureB,
  function(err, stdout, stderr) {
    if (err) {
      assert.equal(stdout, 'A\n');
    } else {
      throw new Error('Preload should have failed');
    }
  });

// test that preload can be used with --eval
child_process.exec(nodeBinary + ' '
  + preloadOption([fixtureA])
  + '-e "console.log(\'hello\');"',
  function(err, stdout, stderr) {
    if (err) throw err;
    assert.equal(stdout, 'A\nhello\n');
  });

// test that preload placement at other points in the cmdline
// also test that duplicated preload only gets loaded once
child_process.exec(nodeBinary + ' '
  + preloadOption([fixtureA])
  + '-e "console.log(\'hello\');" '
  + preloadOption([fixtureA, fixtureB]),
  function(err, stdout, stderr) {
    if (err) throw err;
    assert.equal(stdout, 'A\nB\nhello\n');
  });